Hydraulic jack



Oct. 24, 1950 D, C, KEMERER 2,527,428

HYDRAULIC JACK Fld March 25, 1947 2 SheehS-Sheel'l 1 sroE INVENTOR.

IO BY 'l ldganl!! @TTUPNFV D. C. KEMERER HYDRAULIC JACK Oct. 24, 1950 2Sheets-Sheet 2 Filed Malroh 25, 1947 INVENTOR.

l 'lo l arme/mix Patented Oct. 24, 1950 UNITED .STATES PMENTg OFFICEHYDRAULIC JACK Don C. Kemerer, Santa Monica, Calif.

Application March 25, 1947', Serial No. 737,051

y 3 claims. l

' .This invention relates tohydraulic'jacks and mQIe particularly tojacks;` of this type that. doV

not require air vents or breather valves. v

Various and sundry hydraulic jacks have heretofore been proposed, havingmeans for compensating for the, atmospheric dilerential between theinterior andexterior of the oil reservoir when the oil is pumped fromthe. reservoir into the jack lifting cylinder. The jacks which employvents or breather tubes are objectionable in. that oil leaks out` of thevents when the jacks are used in inclined positions. Such jacks cannotbe stored; or carried'readilyin vehicles such as automobiles.,

The present invention has to do with portable ferring the lifting mediumor liquid between the reservoir and the jack cylinder.

Another object is to provide a jackv having the abovecharacteristicswhereinithe base ofthe jack is formed to provide thepump'cylinder and passageways for transferring the lifting mediumbetweenthe reservoirA and jack cylinder.

Anotherobject is to provide a jack havingl the above characteristicswherein the reservoirvcontaining the lifting medium surrounds the jackcylinder and of such shapeas torender the jack accessible for usein-restricted'areas,

An object, also is to provide a portable, lightweight hydraulic jack inwhich all'internal chambers are at alltimes completely lledwitlr liquidandout` of contact with air,-solthatsludgeformation or` oxidation isprevented.

H Anotherfobject` is to.` provide a hydraulic jack In the drawings:

Fig, 1 is a sectional view taken along the line I--I of Figure 2.

Fig. 2` is a top plan view of a hydraulic jack embodying the invention.

Fig. 3 isa top plan view of the jack base partly in sectionl in order toillustrate certain details of the invention.

. Fig. 41 is a sectional View taken along the line IV--W of Fig. 3, and

Fig. 5A is a sectional view taken along the line V-V of Fig, 3.

Referring tothe drawings a base is generally represented byV the numeralI 0. The base I0 consists of an elongated relatively Wide member whichmay be formed in any suitable manner such as by casting and thereaftermachined` to provide certain features hereinafter to be described. Thefrontend of the base may be-rounded to form a semicircular portion I I.Concentric with' the axis of the semicircular portion is provided anupstanding annular ange I2. The flange I2 is reduced at its upper end asshown at I3, the reduced portion I3 forming a shoulder I4. Within thebase I0- and concentric with the flange I2 is provided an upwardlyextending annular flange I6, the flange I6 being internally threaded forreceiving the lower threaded endV of a jack cylinder represented initsentirety by II. Concentric with the annular flange I6: an annular grooveI8, is provided within the base which forms the bottom of the jackcylinder II-, the annular groove I8 defining an upwardly extendingcenter projecwhich is compact,V capable of being,` introduced under lowobjects and still-be able tolift suchobjectsl to. an appreciableheighteasilyeven though the object Weighs twotons or more.

A further object is to provide ay j ack having the above characteristicsthat will be compact, efficient in operation, simple to construct andcomparatively cheap torlmanufacture.

The above anda other. objects will be apparent throughout the furtherdescription of the invention when taken in connection; with theaccompanying drawings wherein'like-reference characters `refer to likeparts. It is toV be distinctly understood that theV drawings are not adefinition of the invention but merely-illustrate-oneform by means ofwhich` they invention may bev` elicotuated.

tion I9V having a vertical threaded opening 20 therein.l Y Y Attheopposite end of the base I0 to the semicircular portion I I the baseextends in a gradually reduced elongated portion 2I-. Projectingupwardly withinthe contines of the base portion 2| is a relatively wideportion 22 which merges into-an integral with the annular ange I2.Extending inwardlyv and downwardly from the free end and in alignmentwith the vertical plane of'thellongitudinal center of the base isprovided 'a pump cylinder 23, the latter having a piston 24 therein.

Means are provided for actuating the piston 2,4` which consist of spacedupstanding projections 25and 26 disposed at the rear end of the jackbase I0. These projectons 25 and 26 are parallel to and equally spacedonopposite sides to the longitudinal center line of the jack base.

Adjacent the top of projections 25 and 26 are provided openings 2'I and28. These openings 2.u and 2li` are in alignment and adapted to reforreceiving.V the innerend of the handle 33. The' inner end of handle 33may extend into opening 34 and engage the shaft 29 in any suitablemanner such as the bayonet connection as shown at 35.

The jack cylinder I1 is of the telescopic type and in the form shownconsists of three 'tubular' cylinders 36, 31 and 38. The outer cylinder36 is stationary and its lower end is externally threaded for engaging`.the inner threads of the annular ange I6 as shown at 39. The innermostcylinder or lift element is' internally threaded adjacentl its upperendV to receive the externally threaded lower portion of a head orlift-engaging member 48 as shown at 4I. Suitable oil rings between thecylinders 36 andjS1 and between cylinders 31 and 38 are provided asshown at 42 and 43 respectively. Within the innermost cylinder 38 a coilspring 44 is positioned having its upper end connected to the lower endof the head 48 by any suitable means such as shown at the 'nipple 45 andlhaving its lower end connected to the projection I9 by a threaded means46 threaded into the threaded opening 28. The spring 44 operates to biasthe head 48 downwardly and the cylinders 36, 31 and 38 into theirVtelesc'oped position.

The reservoir 41 consists ofA a preformed exible outer wall 48, thelower end vof the flexible wall 48 being positionedto rest on theshoulder I4 and to grasp the reduced portion I3 of the fiange I2. Asclearly shownin Fig. 1, the wall 48 is preformed into a paraboloidalsegment having a lower large diameter and an upper small diameter. Thewall 48 curves inwardly towards its upper end and isv there providedwith athickened portion 49 presenting a face 58 adapted to receive andgrasp the outer surface of the upper end of the jack cylinder 36. Theface 58 may be glued or otherwise xed to the-surfaces of flange I3 andcylinder 36. Wall member 48 may be a preformed or molded member offlexible, tough, vinyl resin or synthetic rubber composition.*Encircling and enclosing the flexible'y'vall` 48 is provided a casingv5I which may be of metal or any suitable material for protecting theflexthe oil to return to the reservoir 41 from the jack cylinder.Referring particularly to Figs. 3 and 5, the piston 24 on its suctionstroke draws oil from the reservoir by way ofpassageway 58 into thecylinder 23., AThe passageway 58 is provided with a suitable valve 59for preventing return of the oil back into the reservoir and on thepower passageways 68 and 6I into the bottom I8 of the the lower end 54of thev casing 5I, resting on the v top of the shoulder 5K2 of the wall48 will Valso tend to maintain the lower end ofthe wall 48 in xedrelation with the shoulder I4 and opposing face of reduced portion I3.The casing 5I, which surrounds and is slightly'spaced from the flexiblewall 48 also terminates at its top with an inwardly extending vroundedportion the upper edge of which may be provided with an inwardlyextending ange 55, adapted to seat on the upper end of the thickenedportion 58 of the wall 48. The case or housing 5I may beheld in positionby a snap ring 56-in groove 51, vthe'ring bearing against flangeor lip55. I

Suitable passageways are provided for the oil pump t'o draw oil from thereservoir 41 and to transfer the oil to the bottom I8 of the jackcylinder and suitable passageways for permitting Abottom of thereservoir.

jack cylinder. The passageway 68 is provided with a suitable valve 62for preventing return of the oil to thecylinder on the suction stroke ofthe piston. An extension of the passageway 6I is provided with a releaseor by-pass valve 63 carried by the end of an actuating rod 64, threaded'bore 65 provided in the side wall'of the base. 'The actuating rod 64 maybe provided with a wing member 64a for rotating the same and opening orclosing the valve 63. A passageway 66, extending vertically within thebase I8 is connected with the passageway 6I by way of valve 63 forpermitting the lifting uid to return to the reservoir. Passageway 66extends upwardly and connects with the interior of the The passageway 66isl also provided with a check valve (not shown) similar to valves 59and 62 are preventing the return of oil from the passageway 66 by way ofthe valve 63 into the passageway 6I. The passageway 58 supplying oilfrom the reservoir to the pump cylinder 24A may be suitably yformed byVertical opening in the bottom of the base, the opening beingcounterbored to receive the springheld check valve 59 and the bottom ofthe opening closed by threaded means shown at 61. Also, the passageway68 may be similarly formed by a bore in the side Wall of the base asshown at 68. The passageway 6I may be an extension of the borecontaining the release valve 64 and the forming of the passageway 66 issimilar and vertical from the bottom of the base as that described inconnection with passageway 58.

The-reservoir may be lled with'lifting fluid by merely removing thethreaded means 69 disposedin the bore at68 and the oil can be pumped byway of the bore '68, passageway 6I, valve 63 and passageway 66 into thereservoir, a pa'rt of which is conveniently supplied to the jackcylinder 38 by-way of passageway 6I. During the lling operation the jackmay be turned bottom side upwards and the predetermined amount of oilrequired injected through the bore 68 to the reservoir :and cylinder 54.It will be noted that all of the space in the reservoir, jack cylinderand passageways can be and is lled with oil. It can now be understoodthat up actuating of the pump handle 33 the yoke 38 carrying the arm 3|will oscillat'e the piston 24 within the cylinder 23; that upon thesuction stroke of the piston 24 4oil will 'be' drawn from the reservoirby way of passageway 58 and valve 59 into the cylinder 23; and that uponthe compression stroke the valve 59 will prevent the lifting medium fromreturning through the passageway 58 and the same will be forced throughpassageway 68, valve 62 and passageway 6I into the bottom I8 of the jackcylindenthe lifting medium operating to extend the telescopic cylindersto the desired distance. When it is" desired to return the lifting head48 to its down position, it is only necessary to open release valve 63whereby the spring 44 will urge the lifting head 48 downward and bringthe jack cylinders into their telescopic operation. The lifting mediumpasses back through the passageway 6I, valve 63, passageway 66 and check'of the jackand enclosed within the base is the pump cylindenpiston andall the required passageways for transferring the lifting fluid betweenthe reservoir and the jack cylinder. The construction and arran-gementof the flanges l2 and i6 makeV possible the recesses 'l0 in the basewhich materially reduce the weight of the base. Ribs 1I may be formedbetween the recess l@ for strengthening the flanges I2 and IS as clearlyshown by Fig. 3.

The base may be further lightened by forming grooves or channels 12, 'i3and 'M in the bottom of the base. The channels in the bottom of the baseform convenient feet for the jack and also provide convenient hand gripsfor carrying the jack from one place to another.

The casing 5| of the jack is perforated in order to provide for freeingress and egress of air to compensate for the flexing of the reservoir68. The wall G8, of paraboloidal form when the reservoir 41 is filled,does not stretch when the reservoir is depleted due to raising of thejack. The casing is preferably circular in cross section and tapersinwardly toward the top and forming a dome-shaped structure which makesfor easy accessibility in restricted places.

While only one embodiment of the invention has been illustrated anddiscussed, it will now be apparent to those skilled in the art thatcertain changes, modifications, alterations, substitutions, additionsand omissions may be made in the construction here illustrated withoutdeparting from the spirit and scope of the appended claims.

I claim:

1. A compact, extensible hydraulic jack capable of being operated in anyposition. comprising: a base; a tubular jack cylinder of substantiallyuniform external diameter mounted on the base, the upper end portion ofthe cylinder being of smaller internal diameter, the inner surface ofsaid upper portion being provided with a groove carrying a sealing ring;a tubular lift element telescopically slidable within the jack cylinderand sealing ring thereof, said lift element being free from sealingrings and including an outwardly extending stop lip at its lower end andan inwardly extending stop lip at its upper end; a central lift elementtelescopically slidable within the tubular lift element, said centralelement carrying an outwardly extending stop lip provided with a sealingring at its lower end and a head at its upper end; a flexible Wallmember, preformed into a paraboloidal segment, having a lower largediameter connected to the base and an upper smaller diameter connectedto the upper portion of the jack cylinder to form a reservoir; a pumpcylinder formed in the base and operably connected to the bottom of thejack cylinder and reservoir; and a body of liquid completely fillingsaid reservoir and pump cylinder in all positions of the .lift element.

2. A hydraulic jack capable of being operated in any positioncomprising: a base member having anintegral upstanding, outer, circularflange and an integral inner, concentric flange, the two flanges beingspaced from each other; a downwardly and inwardly directed pump cylinderformed in the base, the axis of the pump cylinder being directed towardthe axis of the inner flan-ge; an upstanding jack cylinder ofsubstantially uniform external diameter connected by its lower end tothe inner flange; telescoping lift elements slidably mounted within thejack cylinder; a flexible wall member preformed into a paraboloidalsegment having a lower large diameter connected to the outer circularflange of the base and an upper smaller diameter connected to the topportion of the jack cylinder to form a reservoir; conduit meansconnecting said pump cylinder with the lower end of the jack cylinderand the reservoir; an upstanding bracket integral with the baseexternally of the outer flange; an o-scillatable yoke pivotally mountedon the bracket; a piston in the pump cylinder; a connection between theyoke and the piston; and a body of liquid completely lling saidreservoir, pump cylinder and conduit in all positions of the liftelements.

3. A hydraulic jack capable of being operated in any positioncomprising: a base member having an integral upstanding, outer, circularflange and an integral inner, concentric iiange, the two anges beingspaced from each other; a downwardly and inwardly directed pump cylinderformed in the base, the axis of the pump cylinder being directed towardthe axis of the inner flange; an upstanding jack cylinder ofsubstantially uniform external diameter connected by its lower end tothe inner flange, said jack cylinder carrying an inwardly facing sealingring at its upper end; a tubular lift element slidably mounted withinthe jack cylinder, said tubular lift element being free from sealingrings, a headed lifting element centrally disposed and slidably mountedwithin the tubular lift element, said lift elements being in.telescoping relation; a flexible wall member preformed into aparabolodial segment having a lower large diameter connected to theouter circular ilange of the base and an upper smaller diameterconnected to the top portion of the jack cylinder, to form a reservoir;conduit means connecting said pump cylinder with the lower end of thejack cylinder and the reservoir; an upstanding bracket integral with thebase positioned externally of the outer flange; an oscillatable yokepivotally mounted on the bracket; a piston in the pump cylinder; aconnection between the yoke and the piston; and a body of liquidcompletely lling the reservoir, jack cylinder and conduit in allpositions of the lift elements.

DON C. KEMERER.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 884,884 Apgar Apr. 14, 19081,685,697 Guerin Sept. 25, 1928 1,715,901 Countryman June 4, 19291,723,131 Burkholder et al. Aug. 6, 1929 1,990,004 Shannon Feb. 5, 19352,052,781 Lindsay Sept. 1, 1936 2,352,390 Kirkland `June 27, 1944FOREIGN PATENTS Number Country Date 265,867 Great Britain Feb. 17, 1927

